Linux/Unix

CVS Basics

1. Create a Repository:
   

   % cvs -d /usr/local/cvsroot init
   

   -d specifies the location of the cvs repository. If the repository exists on an external server and you want to access it securely using SSH you must first set $CVS_RSH=ssh and $CVS_SERVER=cvs. Consider the server is server.company.com and the cvsroot is at /usr/local/cvsroot and your user account is user.

   % cvs -d :ext:user@server.company.com:/usr/local/cvsroot init
   

   Alternatively you can set $CVSROOT=:ext:user1@server.company.com:/user/local/cvsroot

2. Populate the repository: importing your current project

   Consider your project is in a directory wdir and already contains project files and you want to put the files in the cvs tree under project/rdir

   % cd wdir
   % cvs import -m "Imported sources" project/rdir softco start
   

   softco is the "vendor tag" and start is the "release tag"

   If you want to start a new project from scratch create an empty directory structure and import it as above.

   % mkdir wdir
   % mkdir wdir/src
   % mkdir wdir/doc
   % cd wdir
   % cvs import -m "Imported sources" project/rdir softco start 
   

3. Check out your imported sources

   % cd ..
   % cvs checkout project/rdir
   % diff -r wdir project/rdir
   % rm -r wdir
   

   It is important to remove your original sources such that you don't edit them by accident. Changes made to wdir will not make it into the source tree.

4. Continuing development using the source tree

   When you add new files or directories to your project you must first perform a cvs add and then a cvs checkin. It is a good idea to first perform a cvs up -d before performing a checkin.

   % cd project/rdir
   % touch afile
   % echo "Hello World" > helloWorld.txt
   % echo "THE README FILE" > README
   % cvs add afile helloWorld.txt README
   % cvs checkin
   

   cvs will launch your editor ($CVSEDITOR) for a the log file

   If the source tree is being used by more than one developer or there are multiple copies checkedout (for instance on separate computers) you should always perform a cvs up -d and resolve any conflicts prior to checking in anything. The -d flag downloads new directories if they exist.

   % cvs up -d
   

   Resolve any conflicts.

   % cvs ci
   

   ci is a shortcut for checkin.

5. Tagging and Exporting

   Tagging allows a name to be associated with all files at one point in time reguardless of their individual version numbers. Concider a repository with three source files foo.c, bar.c, and thud.c. foo.c is on cvs version 1.4, bar.c on 1.32 and thud.c on version 1.8 and you are ready to send a release version (1.0) to your customer. Note - the file version mentioned above are CVS version number, not release version numbers.

   Tagging allows an identifing string(tag) to be associated with the three files and their current CVS version numbers. Work(including cvs checkin) may continue the source files thus increasing their CVS version number, however at anytime it is possible to check out the version associated with a specific tag.

   Tag a module with the tag rel_v1_0 by running the following:

   % cvs tag rel_v1_0
   

   To export the module foo with tag rel_v1_0 run the following

   % cvs -d /afs/cs/user/mbz/cvsroot export -r rel_v1_0 module
   

The above instructions are meant to be used as a quick summary and refresher and are by no means complete. Please refer to www.cvshome.org for the complete manual as well as downloads. Users may also run man cvs and cvs --help.